jQuery AJAX JSON data not sending

Question

I have the below code running to send data as a JSON object

var jdata = JSON.stringify(grid.serialize());
$.ajax({
    'type': 'POST',
    'url': 'print.php',
    'data': jdata, //assuming you have the JSON library linked.
    'contentType': "application/json",
    'success': function (data) {
        alert(data);
    },
    'error': function (x, y, z) {
        alert(x.responseText);
        // x.responseText should have what's wrong
    }
});
alert(JSON.stringify(grid.serialize()));

Currenty the alert after the ajax function prints

[{"id":"1","col":"1","row":"1","size_y":"1","size_x":"1"},{"id":"2","col":"2","row":"1","size_y":"1","size_x":"1"}]

On the receiving page I am using <?php print_r($_POST) ?> to see what the page is being sent and it keeps outputting

Array
(
)

I must be missing something simple but have been unable to figure out what. Maybe a fresh set of eyes will see a simple mistake I have made.

Just a quick guess... I think you must write post in lowercase. Otherwise... did you try with `$.post`? — crackmigg, May 18 '13 at 12:12
Are you posting `[{"id":"1","col":"1","row":"1","size_y":"1","size_x":"1"},{"id":"2","col":"2","row":"1","size_y":"1","size_x":"1"}]` as is? — Raz Harush, May 18 '13 at 12:13
Launch Fiddler, http://fiddler2.com, or a similar tool to examine your form Post. — nickytonline, May 18 '13 at 12:15
@Bimal: The problem here has nothing to do with cross-domain issues. — Felix Kling, May 18 '13 at 12:30

score 2 · Accepted Answer · edited May 23 '17 at 12:28

2

I think $_POST is only populated if you send the data encoded as x-www-form-urlencoded. So, just assign the JSON string to a key (jQuery takes care of encoding it properly):

'data': {data: jdata}

and remove the 'contentType': "application/json" part.

Then you get the data in PHP with:

$data = json_decode($_POST['data'], true);

Alternatively, get the raw body of the request in PHP and process it: How to retrieve Request Payload

edited May 23 '17 at 12:28

Community

1
1

answered May 18 '13 at 12:17

Felix Kling

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I tried this method and it passes the json array but backsashes a of the double quotes – Somk May 18 '13 at 12:27
Then you should probably disable magic quotes: http://stackoverflow.com/questions/6642901/php-5-3-automatically-escapes-get-post-from-form-strings – Felix Kling May 18 '13 at 12:28

score 0 · Answer 2 · answered May 18 '13 at 12:27

0

If you are sending JSON to the server, on the back-end grab your JSON using:

json_decode(file_get_contents('php://input'));

It won't be in the $_POST super global.

answered May 18 '13 at 12:27

anomaaly

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15

jQuery AJAX JSON data not sending

2 Answers2